Design Of Stereo Laparoscopic Real-time Display System Based On FPGA

Due to small trauma, quick recovery and so on, laparoscopic minimally invasivesurgery is well received by patients. However, traditional laparoscopic system has nodepth information and only provides two-dimensional plane image to the doctor, thusthe potential risk of the surgical operation is increased. With the development ofminimally invasive techniques, the binocular stereo laparoscope has been emerged toimplement three-dimensional visualization of the surgical field. By now, the techniqueof foreign-related products is relatively mature, but there are also some problems likelarge volume and high price. In the current domestic research on stereo laparoscope, thehardware platform is backward, the function is relatively single. In addition there is amore prominent problem on the3D visual effect in three-dimensional laparoscopicsystem. Existing systems often use two optical system placed in parallel structure,which has many advantages but also have a three-dimensional distortion, and the defectof visual fatigue. Visual effect has a direct impact on the doctors’ surgical operation, sothe above problems should be avoided. However, the research in this area is relativelymissing.Based on above problems, the visual fatigue and distortion were studiedrespectively. And the improvement of stereo effect and linear distortions eliminationschemes are proposed. After that, the paper presents the development of a stereolaparoscopic real-time display system based on FPGA. This system gives full play tothe performance of FPGA chip in strong parallel processing ability and rich logicalresources, to complete all of the following tasks, including image acquisition,processing, transmission and display, without the need of the additional control andprocessing chip. As a result, the cost is reduced and a portable design with small volumecan also be realized. Through wearing a pair of shutter glasses，doctors can convenientlywatch optimal abdominal internal stereoscopic images in3D LCD.The experimental results indicate that this system has showed the strong real-timecharacter and the functions of image freeze,2D/3D switching, camera function.Moreover, it has a good synchronization between3D LCD and shutter glasses. Theoptimization scheme is verified on the self-developed system. Three-dimensional effectis improved significantly, and the linear distortion is eliminated, which confirmed the feasibility and reasonableness of the scheme.